It has been a long sought goal, particularly for industrial establishments, such as hotels, to have a bathtub which is automatically cleaned after use. Such prior attempts have not been sufficiently practical and efficient to be implemented in general usage.
For example, in a patent to the present inventor, U.S. Pat. No. 4,383,341 issued May 17, 1983, a spring loaded series of spray nozzles were used to spray the sides of the bathtub. However, the device, with the numerous elements, was difficult to manufacture and was also inconvenient to use, since it required that cleaning detergent be added prior to each use.
Such disadvantages made it difficult to economically and reliably manufacture the self-cleaning bathtub, and also made the use of the bathtub less than desirable.